A Study of ALRN-6924 for the Prevention of Chemotherapy-induced Side Effects (Chemoprotection)

During Part 1 SCLC, topotecan will be administered per standard practice on Days 1-5 of 21-day cycles. Patients will be randomized to receive 1 of 2 initial ALRN-6924 dose levels, to be administered prior to each planned topotecan dose. The incidence, severity and duration of hematologic toxicities, including neutropenia, thrombocytopenia, and febrile neutropenia, will be determined. The safety and tolerability of each ALRN-6924 dose level will be assessed during Part 1. ALRN-6924 is given either 24 hr or 6 hr prior to each topotecan administration. Part 2 NSCLC of the study will be conducted in two stages. In Stage 1, a total of 20 patients will be randomized 1:1 to receive (with or without immunotherapy) either carboplatin plus pemetrexed plus ALRN-6924 or carboplatin plus pemetrexed plus placebo. During Stage 1 of Part 2 NSCLC, two interim analyses will be conducted after 10 and 20 patients, respectively, have been evaluated. The purpose of the two interim analyses is to confirm safety and exclude futility. In Stage 2 of Part 2 NSCLC, an additional 40 patients will be randomized to treatment as described for Stage 1. Immunotherapy and/or bevacizumab may be used concurrently with chemotherapy and after completion of 1st-line treatment (i.e., for maintenance purposes) as per local standard of care. Time of administration of immunotherapy and/or bevacizumab relative to chemotherapy will follow local standards of care.